OFFSET
2,1
COMMENTS
Conjecture: all the terms are in A121707. If k is a term, then k is an "anti-Carmichael number": p-1 does not divide k-1 for every prime p dividing k.
The sequence is unbounded, since a(m!) > m.
Prediction: a(n) < n for all sufficiently large n.
GCD(n, a(n)) = 1. a(n) is odd. Is a(n) squarefree? - David A. Corneth, Aug 13 2018
PROG
(PARI) a(n) = {my(k=2); while (gcd(k, n^k - n) != 1, k++); k; } \\ Michel Marcus, Aug 13 2018
(PARI) a(n) = {my(k=3); while (gcd(k, n^k - n) != 1, k+=2; while(gcd(n, k) > 1, k+=2)); k} \\ David A. Corneth, Aug 13 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Thomas Ordowski, Aug 13 2018
EXTENSIONS
More terms from Michel Marcus, Aug 13 2018
STATUS
approved